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PTS Engine and Airframe Paperwork
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CERTIFICATES AND DOCUMENTS; … The Aircraft; …Category; … Sequence of Decision for Airworthiness; … FAR 91 Aircraft equipment required; … OBTAINING WEATHER INFORMATION; … CROSS-COUNTRY PLANNING; {Required  Reference Papers)  ...DETERMINING PERFORMANCE AND LIMITATIONS; ...Performance Sheet ASEL; ...Cross Country Flight Plan; ....OPERATION OF AIRPLANE SYSTEMS; MINIMUM EQUIPMENT LIST; ...Permanent Records; ...Engine Logs; ...Inspections; ...Getting an MEL to Use; ...Operating without a (MEL); MEL Decision Sequence; Repairs; ...Airworthiness Directives (ADs); ...Service Difficulty Reports (SDRs); ...Service Bulletin; ...Maintenance Records; ...Airworthiness Directive; Pilot/Owner Maintenance; ...Most Dangerous Thing in Aviation; ...Partial MELs; ...Guide for Best Maintenance of Aging Aircraft; ...


REFERENCES; FARs 43, 61 and 91; AC 61-21, AC61-23; Pilot's handbook and Flight Manual

P Locate and use aircraft and personal papers and records.

EX Pilot privileges and limitations, medical certificate, log book requirements, biennial, radio license, airworthiness, registration, station license, placards, manual, weight and balance, maintenance records. A private pilot, when current and qualified in a properly equipped aircraft can fly anywhere flight is allowed or clearance given, except for hire. The pilot must know and follow the Federal Air Regulations (FAR's). He must have a current medical certificate and have logged the required three takeoffs and landings in a specified type/class of aircraft for both day or night (full stop) as determined for the flight. Two years subsequent to licensing, he must pass a flight review and have it entered into his logbook. A radio license is no longer required in the United States but is required otherwise.

The FAA calls the pilot's license a "certificate". It is one of several kinds, including the flight instructor certificate. The certificate is in two parts.

1) Definition of privileges

2) Ratings that specify kinds of aircraft to which the privileges apply.

A student pilot certificate allows solo flight. The aircraft ratings are added by the instructor for each aircraft. The private pilot certificate adds the privilege of carrying passengers not for hire. Additional ratings to the private certificate are instrument and any category, class or type. You are expected to know the varieties of ratings available. The commercial certificate allows flying for hire except were FAR 135 or 121 strictures must be met.

A private pilot, when current and qualified in a properly equipped aircraft can fly anywhere flight is allowed or clearance given, except for hire. The pilot must know and follow the Federal Air Regulations (FAR's). He must have a current medical certificate and have logged the required takeoffs and landings in a specified type/class of aircraft for both day and night as determined for the flight. Two years subsequent to licensing, he must pass a flight review and have it entered into his logbook. A radio license is no longer required in the United States. Get a radio license before going to Canada or Mexico.

Ratings identify the aircraft specified as a category and class. There are four categories: airplane, rotorcraft, lighter-than-air, and glider. The first three are divided into classes. Airplane classes are single engine land, multi-engine land, single-engine sea and multi-engine sea. Rotocraft are either gyrocoper or helicopter. Lighter-than-air is airship and free balloon. A type rating is required for aircraft over 12,000 pounds, jets and some parts of FAR 121 and 135. (See AC 61-89B)

Any earned pilot certificate can serve as a student certificate in learning to fly a different class or category. This means you can use your Private Pilot certificate to learn to fly a helicopter. The instructor endorsements are made in the logbook instead of on the certificate.

The Aircraft
Make, model, serial number and "N" number can identify an aircraft. You should know the year the aircraft was built and any major ADs that have applied since it was built.

The aircraft acquires an airworthiness certificate when built or when undergoing major repair. If the required inspections have not been made the airworthiness certificate is not valid. Every aircraft is required to have an annual inspection. Any aircraft used for instruction, compensation or hire is required to have 100-hour inspections.

As issued the certificate remains valid as long as the aircraft is maintained per FARs 43 (maintenance) and FARs 91.
--After manufacture, the FAA may issue Airworthiness Directories (ADs) to correct perceived flaws. 
--ADs amend the original airworthiness by requiring FAR compliance. 
--This may be by structural change, maintenance, inspection, or placard. 
--An AD may require immediate, recurrent or delayed compliance.

Non-compliance renders the aircraft unairworthy and may void insurance coverage. The aircraft owner is responsible for AD compliance. The pilot must know where to find the AD compliance list and should talk to a mechanic as to the interpretation of its codes. The requirement for this knowledge is barely recognizable in the PTS but it is there.

FAR 91.213 has to do with MELs (Minimum Equipment Lists) 91.213(d) applies to aircraft without MELs. AC 91-67, Minimum Equipment Requirements for General Aviation Operations Under part 91. Essentially, those aircraft not having MELs must comply with the original operating equipment when the aircraft was certified as airworthy. Once the aircraft's type design data have been established, they are published in an Aircraft Specification Sheet or Type Certificate Data Sheet. The data on these sheets apply throughout its operational life.

FAR 91.405 directs the owner/operator to have discrepancies repaired or placarded as permitted to be inoperative by 91.213(d)(2) until the next inspection and placarded until then as required by FAR 43.11.

Normal Category is a certification category. This category has a maximum G loading of +3.8 G's (positive G's) -1.52 G's (negative G's). Usually spins and other maneuvers that exceed the normal flight envelope are prohibited.

Utility Category is a certification category. This category has a maximum G loading of +4.4 G's and -1.76 G's. Aircraft in this category are approved for maneuvers that are not acceptable in the Normal category. Spins are required for certification in the Utility category.

Frequently aircraft are certified in the normal category at published gross weights. The same aircraft may also have a certification in the Utility category with different weight and CG limits.. The category it falls into is dependent on it's weight and CG location. The 150 is a utility category aircraft up to it's gross weight. The Acrobat models are single certified in the acrobatic category. The 172 is certified in both categories (at differnt gross weights).
Highflyer et al

Sequence of Decision for Airworthiness
Is it required by FAR 91.2095 or 91.213(d)(2)(ii)
If not Is it required by VFR-day type certificate requirements
If not Is it required by Airworthiness Directive?
If not Is it required by FARs 91.107, 91.171, 91.185, 91.205, 91.207, 91.209 or FAR 91.213(d)(2)(ii)
If not The inoperative must be removed or deactivated by a qualified mechanic and placarded as "inoperative". All work done must be logged and if removed the weight and balance must be calculated and corrected. FAR 43.9

Depending on flight conditions certain basic instruments are required. The groups are flight, engine, navigation and communication. If any required instruments are missing it is up to the pilot to determine the legality of flight. In general, if the aircraft received its airworthiness certificate with a device installed and operational, then it is required for every flight.
FAR 91.213 (a) Vs (d) says that you may (or may not) takeoff in an aircraft depending on how it meets four equipment requirements.
Non-turbine and without a master Minimum Equipment List. (MEL)
Item not required by FAR, MEL, or AD
Item removed or deactivated, placarded, maintenance log entries made, dated and signed by qualified and certified technician. The technician must determine that (3) above is not a hazard.

FAR 91 Aircraft Equipment Required
VFR minimum equipment: airspeed, altimeter, compass, tachometer, fuel gauge, oil temperature, oil pressure, (gear indicator and manifold pressure)
VFR minimum equipment: Position lights, beacon, power source, and a flashlight. Class D airspace requires a radio while Class C and B requires radio, and an encoding transponder.
required above 10,000' in TCA, in ARSA, and above ARSA. FAR 91.413 requires the transponder to be checked and certified within the preceding 24 calendar months.
requirements change at 12,500, 13,000, and 14,000
High altitude
checkout required to fly pressurized aircraft.
Emergency Locator Transmitter
(ELT) is required on all aircraft with some exceptions. FAR 91.207. 50 nm training flights are exempted. The ELT battery must be replaced after one hour of use or on a date of expected half-life. The ELT must be placarded and signed as to date of installation and the expiration dates of this half-life. The logbooks also require a signature by an Airframe & Power Plant (A&P) for this information. As a pilot you must know where to find this information.
IFR flight
has specific checks of VORs, altimeters, and static systems.
is required for legal ownership. The only way to be sure of registration is to check with the FAA Aircraft Registration Branch, in Oklahoma City. Every three years the validity of this registration must be confirmed to the FAA. FAR Part 47. This is a very neglected part of aircraft paper work. Registration expires according to Advisory Circular 61-23B after any of the following:
(1) Replaced by foreign registry
(2) Aircraft destroyed/scrapped
(3) Request to cancel
(4) Holder loses U.S. citizenship
(5) 30 days after death of holder
(6) Transfer of ownership
(7) Registration expires if owner leaves country for 6 months. A waiver of this expiration can be obtained.

Placards or manuals
must be in every aircraft, giving the performance limitations of the aircraft not limited to maneuvering speed, gross weight, prohibitions, and performance. Color-coded markings on the instruments are part of the limitations. Color codes on the airspeed indicator show never exceed speeds, normal operating speeds, flap operating speeds, and turbulent air limitations. The tachometer shows never exceed RPM, and sometimes ranges to be avoided for continuous operations. Normally, you wouldn't need a specific document, on file with the FAA, listing the operating limitations for a specific model aircraft.

Weight and balance
papers are specific to each aircraft and must be available. Any subsequent items permanently affixed to the aircraft must be added as weight and balance elements to the papers. It is a violation of the FARs to operate an aircraft in non-compliance of the operating limitations of the airworthiness certificate. Some aircraft manuals (Mooney's) are required equipment.

Airframe and engine
logbooks must show all maintenance performed. Any aircraft used for instructional purposes must have 100-hour inspections. All aircraft are required to have annual inspections. Minor maintenance may be performed by other than a licensed mechanic. It is a violation of the FARs to operate an aircraft in non-compliance of the operating limitations of the airworthiness certificate. The recommendations of manufacturer bulletins and the operating handbook regarding maintenance should be followed. FAR 91.407 requires a flight check and aircraft sign-off for any maintenance that changes flight characteristics. During the test you will be expected to know the location, requirements, and terminology of these logs as well as to explain the numbering system and meaning of each column on the AD chart.

Go through both the airframe and engine logbooks and post-it the last annual, inspection, the last 100-hour, the last ELT entry, the last transponder entry, and any supplemental modifications made.

Consider the CHECKLIST a required document.

REFERENCES: AC 0-6, AC 00-45, AC 61-21, AC 61-23, AC 61-84 and AIM
P Read reports, charts, forecasts, NOTAMS, PIREPS, AIRMETS, and SIGMETS. Makes considered decision.
EX Total data required for flight, winds aloft, visibility, weather, turbulence, airport conditions, surface winds, and flight restrictions. (You may expect to interpret any one of the charts in AC 00-45C during the oral part of the flight test)

Winds aloft vary with altitude. It is necessary to select the wind and altitude combination most favorable to the flight. Generally you want to fly high with tail winds and low with head winds. Forecast winds are used to find estimated headings and ground speeds for planning purposes. These are adjusted in flight for actual conditions. Winds are never exactly as forecast.

Visibility and aircraft performance helps you select checkpoints at practical /useable distances. Visibilities less than three miles require flight in uncontrolled airspace 700'/1200' AGL. Lower visibilities, sometimes caused by sun position, ceilings, or terrain, makes planning for airport arrivals more difficult.

Cloud conditions can prevent flying at the most preferred altitude. 1000 over/500 below limits may make necessary a higher or lower than optimum altitude. Fog ceilings may make it necessary to be off course when departing. Do not plan any flight, which may take you on top of worse than scatted clouds, into worsening weather, or between cloud layers.

Turbulent conditions, such as below scattered clouds may make flying above them more desirable. Passenger comfort and aircraft control are the limiting factors. High winds cause terrain induced turbulence which are given in AIRMETS, and SIGMETS usually as occurring below a certain altitude. If flying in turbulence, it will be less severe at slower speeds. Visualize a light car Vs a heavy car crossing railroad tracks as how weight and speed affects turbulence. Light turbulence rocks things, moderate slides, heavy jumps. The yellow caution range of the airspeed indicator should be avoided usually and never entered during turbulence.

Airport conditions are a seldom requested element of a weather briefing. Every airport periodically undergoes construction shutdowns or modifications, which are part of required flight knowledge. The FSS is supposed to have this information. The existence of temporary obstructions may require a change in arrival procedure. A phone call to your destination is cheap insurance.

Knowledge of surface winds helps you plan both your departure and arrival. By having some idea of winds you can pre-plan your turns to checkpoints, communications, and the arrival process. Crosswinds may exceed the capabilities of your aircraft thus effectively canceling the flight. NOTAMS must be requested. They may include restrictions to flight related disaster areas, presidential parties, military activities, or air shows. Failure to acquire this knowledge prior to the flight could create serious flight test problems since the examiner probably knows of them.
See instructional material on SVFR (Special Visual Flight Rules) and flight in marginal conditions.

REFERENCES: AC 61-21, AC 61-23, AC 61-84, Charts, A/FD, AIM

P Obtains weather briefing, use of sectional, plotting course, checkpoint selection, computes time/heading/fuel, selects radio/nav aids, identifies airspace/terrain/alternatives, uses proper publications, completes navigational log, files flight plan, shows knowledge and accuracy.

EX Items to be covered in weather briefing, sectional data available, elements of navigation, checkpoint criteria, route and altitude factors, frequency log, alternative options, availability of AIM, complete navigational log, transfer of essentials to sectional,

(You will be given a flight to plan and time to do the planning. I would suggest getting a DUAT briefing along several routes ahead of time. Be able to explain how to obtain any figure required and its significance. Know the charts and radio frequencies.) Get NOTAMS ahead of time.

Give the briefer your complete call sign, time and route of flight. Ask for a complete briefing, record it if you can but tell the briefer. All briefings are recorded by the FSS. Ask for and get surface winds at en route airports and destination, freezing level (Z-level), expected fog conditions, and NOTAMS. The complete briefing will include synopsis (big picture), winds aloft, flight conditions, area forecast, sequence reports, terminal forecasts, and radar summary. It is now possible to use a home computer to get the entire flight planned using a modem. By getting a broad briefing before meeting the examiner you can save yourself time that may be spent on FSS phone 'hold'.

Knowledge of the current sectional must include all elements on the legend, reference to the tower frequency tab on back of legend, use of directions for transferring course lines to both sides, game reserve restrictions, and data related to restricted areas. You should be able to locate any point from designated latitude and longitude and to use distance markings correctly.

You must proceed systematically. Use a pre-prepared scratch form to enter data from differing sources, FSS, manual, sectional, aircraft and computer. Wind direction and speed, TAS, TC to compute GS and TH, then variation and deviation. Be sure to have a copy of the deviation card from the aircraft. Transfer the data to your navigational log.

Select and mark your checkpoints using aircraft performance, visibility, and usability. Skill developed in training can save time. Determine minimum safe and appropriate cruise altitudes with call up/descent point.

Easy as pie using the following technique:

Start from your destination and find  checkpoints or VOR radials as near 90-degrees to route as you
can that will make all the checkpoints evenly spaced.  CAN be done but takes some flexibility as to distance.  Distances are best from 10 to 20 miles depending on aircraft speed. 
Make all the checkpoint distances the same beginning at the destination.  Only the distance from your starting point and the first checkpoint should be different.  
Fly to your first checkpoint and note time, time to second checkpoint gives you basic time for all the equally spaced distances to follow.  Ten spaces at seven minutes a space etc. See my web site under Cross-Country Planning

Make a columnar frequency log for each com/nav radio. Arrange the frequencies exactly as you expect to use them and add supplementary frequencies to the side. Transfer this to a card that can be placed in view while flying. Use the card to keep the radio "ahead" of the airplane where practical.

Since it is unlikely that the entire course will be flown on the flight test, study the sectional. Plan for options, limitations, and factors. Have pattern altitudes of nearby airports on sectional along with frequencies and runway numbers. Get the use of an AIM from a subscriber. A back issue may satisfy the examiner if you let him know that the tower has a current edition available for pilots. Some airport offices also have the AIM. It is best for you to become familiar with its format and contents ahead of time. You may be expected to locate specific information contained in the AIM.

Complete the navigational log with time/distance/ ground speed/fuel use estimated between checkpoints. Transfer MC to the sectional course line along with fuel tank changes, VOR radial numbers, and descent/call up points. Fold sectional so that it is immediately available along with the radio log. The complete navigational log should be on a clipboard. You should make initial entry of times on the sectional and then transfer them to the nav-log. Have extra pens and pencils. Some of them could be hung from the clipboard by strings. Arrange your CHECKLISTS for convenient use.


REFERENCES: AC 61-21, AC 61-23, AC 61-84, Airplane Handbook and Flight Manual

P Figure weight and balance, takeoff, climb, ceilings, range, fuel consumption, TAS, altitude performance, locate all V speeds, landing performance, and final determination of aircraft capability.

EX Effects of weight, effects of balance, ground roll and clearing 50', altitudes effect on fuel, meaning of TAS, meaning of service ceiling, significance of all V speeds, use of flaps, airspeed indicator, RPM, and way of determining capability.

(You must be able to locate any information related to the aircraft.
You may be asked to apply selected data to any one of the charts.)

Performance sheet ASEL
Compute weight and balance with gross takeoff weight___________ Center of gravity location ________
Gross landing weight __________ Center of gravity location _________
Shift weight from _________ to the _____________New center of gravity locaton _________

Cross Country Flight Plan
Total distance is __________Total time is ____________Total fuel used is __________

Total fuel remaining including reserve ___________Is a fuel stop required for this flight? ____

Plan takeoff over a 50’ obstacle at full gross weight at sea lever with an outside air termperature of 30 degrees centigrade ____________

Discuss density altitude and performance.
Plan a landing over a 50 foot obstacle at landing weight at 3000’ pattern altitude with an a standard outside air temperature.

Whis is the best endurance altitude and power setting for this aircraft? _________

What is the range of this aircraft at 75% power? ________ amd 65% power?_______

Weight affects the stall speed of an airplane. Book figures are at gross weights. An overweight plane will stall before the book figure; a light plane will stall at a slower speed. Flight in excess of gross weight is prohibited. Alaska allows 10% over for survival gear. Most aircraft are close to gross when they have full fuel. Reduction of fuel load is the best adjustment factor.

Controls are designed and certified to perform properly within a certain balance/speed range. Va or maneuvering speed (abrupt control movement allowable) is published for gross weight only. An out-of-balance plane at low speeds may not have the effectiveness required for control. This means that the elevators may not be able to properly raise the nose of an airplane while taking off or landing. They may not be able to effectively lower the nose in climb, slow flight or landing. All performance figures are predicated on a properly balanced aircraft. An aircraft that is out-of-balance causes performance figures to change for the worse. This is especially true regarding fuel consumption.

Takeoff data is figured for standard conditions with factors added for wind velocity and runway conditions. Since conditions are seldom standard, you must compute any effects of density altitude or non-standard conditions. Climb is figured likewise. The performance increases at roughly the percentage of the weight reduction. Fly 10 % below gross weight expect takeoff climb and range to improve about 10%.

Fuel consumption may be determined by power applied. Altitude normally decreases the air available to the fuel mixture making possible a reduction (leaning) of the mixture. At altitude the engine has less power and consumes less fuel while at the same time getting more distance. In no wind/tail wind conditions it is more economical to fly high. Density altitude conditions affect fuel/air relationships as well. Fuel consumption, leaned, is about .44 pounds of fuel per hour per horsepower. For the C-150 this gives, .44 X 100 hp /6 lb. per gal = 7.3...gallons per hour. With 22.5 useful capacity and the tanks not really topped off (prevents waste) three hours flight time with the required 1/2 hour daytime reserve comes up short. The manual gives more optimistic figures predicated on lower horsepower available at altitude.  Don't TRUST the manual.

The true air speed (TAS) is calibrated airspeed (CAS) corrected for air density. This is the manufacturers manual speed, which you use for navigational purposes to find ground speed. For practical use it is too optimistic due to the differences between new and abused (sic) aircraft. The service ceiling is required knowledge since it makes no sense to plan a flight across terrain above aircraft capability. At service ceiling the plane can still climb 100 feet per minute. Density altitude factors can greatly affect both this ceiling and the absolute ceiling.

The V speeds are determined through exhaustive study by the manufacturer to be the best speeds for a specific desired performance. While these speeds may vary somewhat with aircraft weight they are required knowledge as a base for performance. V speeds are indicated speeds, which are to be flown within the ranges, specified in the Practical Test Standards. V speeds are usually found near the front of the aircraft annual with explanation. It is best to locate, and know for the flight test, the significance and number of all the V speeds such as: Vx, Vy, Va, Vne, Vfe, etc.

Broad performance - specifications of the aircraft are on back of the front cover or on the first few pages of the manual. For specific performance under conditions see the chapter index. Putting labeled tabs on certain charts related to takeoff, landings, emergency, and power settings would make location easier. FAR 91.103 requires that we calculate required runway lengths for takeoff and landing. You need not know everything in the manual but you must be able to locate desired information efficiently. It is not recommended to ever fly without a manual available and may be a violation of the FARs. Va, maneuvering speed, is slower at lighter weights. So are stall speeds. The maneuvering speed is a limit on control movement. Since the aircraft loading moments between control pressures and turbulence pressures differ, the allowable turbulence speed may be a bit higher than Va.

Since the use of flaps and slips varies so widely between aircraft, it is important to know what is specifically required, permitted or prohibited for your aircraft. The stronger the cross winds the fewer degrees of flap recommended. The maximum demonstrated crosswind component is not a limitation. It is something required as a demonstration. Make sure to know under what conditions slips are allowed or not. For takeoff be sure to know the required flap setting for specific performance. Partial and full flap settings may have different airspeed limits. Application of flaps before slowing to required speeds will be harmful to the aircraft. The way flaps are removed in flight depends upon the airspeed. Below Vx they should be milked off slowly until Vy is obtained while holding altitude. At Vy or higher removing the flaps all at once should not create a problem.

It is advisable to have your own manual for every aircraft you fly.


REFERENCES: C 61-21, AC61-23, Airplane Handbook and Flight Manual

P 1. Explain aircraft systems and operation.

Ex Controls, flaps, trim, engine, instruments, landing gear, engine, propeller, fuel system, hydraulic system, electrical system, environmental system, icing, navigation and communications, and vacuum system.

The ailerons, elevators, and rudder are usually moved via a system of cables and pulleys connected to a yoke or stick. In some instances a system of push rods may be used. Flaps and spoilers may be operated by push rods or electrically. Trim may be manual, electrical or both. High performance aircraft may have hydraulic or electric boost systems to aid the pilot.

Flight instruments have several modes of operation. The compass is magnetic. The ball is gravitational and inertial. The needle or turn coordinator is usually electric gyro driven. The attitude and heading indicators are usually gyro driven by vacuum pressure. The altimeter, airspeed indicator, and vertical speed indicator are functions of outside air pressures. Examiners have been known to cover or otherwise disable instruments.

Landing gear, fixed or retractable, have shock absorbing springs, air/oil struts, or rubber in combination to take the shock of landing. Retractables may operate manually or electrically with visual or lighted indicators as to gear position. Higher insurance and maintenance costs go with retractables.

Brakes are usually hydraulically operated shoes clamped to the brake disk attached to the wheels. Hydraulic cylinder connected to the top of the rudder pedals allows toe pressure to operate the brakes. Retractable gear has similar braking systems. Aircraft tires are usually of natural rubber and have a four-ply rating but only two plies. This means that when you can see the beginning of cord in a tire it is absolutely time to quit using it. The nose wheel regardless of its suspension system allows the application of foot pressure on pedals and brakes to provide ground steering. Good operational techniques would use the nose wheel only during the very slowest part of takeoff and landing.

Most light aircraft engines are four stroke, (intake, compression, power and exhaust), horizontally opposed, and gasoline fueled. Each cylinder has a spark plug on top and bottom, which obtain an igniting, spark from dual magnetos. Each cylinder has an upper and lower spark plug. The magneto serving the top right plugs services the lower left plugs.

Spark plugs fouling from fuels with lead would be caused at low power settings where the internal cylinder temperature was not high enough to vaporize additives. Small lead pellets would form in the lower plugs and cause preignition. When unleaded fuels are used the deposits are calcium like particles that cause preignition (knocking in automobiles) by shorting out the spark plugs. Avoid low power descents and power off operations. During taxi be assure to lean so as to avoid lead fouling. At shut down the rpm may be increased momentarily so as to facilitate removal of any accumulated fouling. Preignition is shown by engine roughness, backfiring and high cylinder head temperatures. Detonations occur as a result of ignition of unburned combustible material by pressure or temperature.

1. Copper runout or lead fouling = excessive heat;
2. Carbon and lead bromide deposits = low temperature and excess richness.
3. Oil fouling shows piston ring problems and wear.
4. Other than brown/gray deposits = incomplete combustion
5. Cracked porcelain = preignition
6. Carbon fouling = valve guide or ring wear and oil burning.

The controls for the engine are few. The throttle moves a wire connected to the butterfly valve of a carburetor engine and controls the airflow drawing fuel to the engine. Pumping the throttle can fill the carburetor as a priming method. Over use of this priming can cause the fuel to over flow and start an engine fire. The fuel injected engine throttle performs a similar function but provides better fuel distribution. A fuel-injected engine cannot be primed by pumping the throttle.

The venturi effect of a carburetor air intake can cause any moisture in the air when mixed with fuel to form ice and adhere to the interior of the venturi. This ice can choke off the flow of air to the carburetor. This is most likely to occur at low power settings but can occur at any time even on very warm days. The symptoms of carburetor ice are insidious but start with unexplained loss of RPM or manifold pressure accompanied by roughening engine operation. Since this condition arises from conditions outside the aircraft, correction rather than prevention is the control method.

Application of carburetor heat opens a diversion gate in the heater- exhaust system and cuts off the outside air intake while diverting hot air into the carburetor. The hot air causes an additional drop in RPM or manifold pressure and a rise as the ice melts. Removal of carburetor heat will give an additional rise in RPM and manifold pressure. Fuel injected engines do not have carburetor heat controls.

Air and fuel are mixed by weight. About 16 pounds of air to 1 pound of fuel gives best power. An engine can intake only so much air depending on the volume of its piston cavity. As the density of the air decreases with altitude the air molecule intake into the engine decreases. The 16 to 1 air fuel ratio becomes over-rich with fuel and power decreases. The mixture control allows the pilot to adjust the air/fuel mixture for the best power for the air available. Even so the power of a normally aspirated engine decreases with altitude. It is possible to install an air pump called a turbocharger which will pressurize the air being taken into the cylinders and make possible more fuel consumption and greater power.

Most light aircraft have a fixed pitch propeller, which is a compromise pitch between a climb or cruise propeller. A constant speed propeller has an additional cockpit control, which allows the pilot to use oil from the engine to adjust the pitch for best climb or cruise. The setting of the control causes the propeller to maintain a constant RPM.

The airplane can operate much like a lawn mower. Just turning the propeller can give the electrical spark needed for operation. It is this feature which makes ground operation so dangerous. A shorted magneto or fuel left in the carburetor could cause any small movement of the propeller to start the engine. For these reasons the engine shut down should include a magneto check and fuel starvation. The checking of the magnetos prior to takeoff should be as recommended in the POH (Pilot's Operating Handbook). Checking at a lower RPM may cause a higher than normal magneto drop, giving a false indication of trouble. A minimal or nonexistent drop should raise suspicions of a "hot" or shorted magneto. Hot magneto checks should be done at RPMs less than 800. A momentary turn to "off" should show whether the engine is going to stop (as it should) before returning to "both".

Gasoline is the fuel for airplanes. The fuel is enclosed in metal or rubber tanks, which have cockpit gauges to indicate either weight or quantity. The safest method to judge fuel is by time. All low wing aircraft have electric fuel pumps as a backup for the engine driven pump. High wing aircraft do not usually have auxiliary pumps since the gravity flow is considered adequate. All aircraft have a cockpit operated shutoff valve for gasoline to the tanks. Most aircraft have fuel tank selector valves associated with the shutoff valve. Low wing aircraft normally select single tank operation while high wing aircraft select both tanks.

Every aircraft engine is designed for a specific grade of fuel. Only this grade or a higher grade should ever be used. All grades of fuel have different colors. The mixing of grades may give a colorless mixture. The smell of the also colorless jet fuel is an important safety check. Since the fumes of gasoline are very explosive the aircraft should be grounded during fueling to prevent and static electrical discharges. It is very possible to get widely varying amounts of fuel into an aircraft tank depending on the how level the ground. A level engine can make a difference of 1/2-quart reading in the oil level.

Fuels were once available as 80/87, (red) 91/96 (blue) and 115/145 (green) octane. The first two of these have been replaced by 100LL (blue)(low lead). With some changes in maintenance low compression engines can use 100LL with no problem. Because of exhaust valve damage and valve guide wear of 100/130 (green) can only be used with lead scavenging additives. Where carburetor icing is a problem, certain anti-icing additives are available to be used only after consulting aircraft manufacturer as to compatibility with fuel tanks.

Automotive fuels must have STC (supplemental type certificate) for the specific aircraft and engine before use. Such fuels may cause preignition, detonation, vapor lock and valve problems. Specific brands of fuel differ in their properties and composition. Aircraft filler openings must be marked as to minimum grade to be used.

The hydraulic system of most small aircraft applies mostly to the brake system. Since brake application puts very high pressures on the lines and hoses it is vital that the preflight check for any hydraulic fluid leaks. These leaks are best noted by the accumulation of oily dirt.

The engine also may have accessories. A battery-powered starter can turn the propeller. An engine driven generator or alternator will give enough electricity for lighting, radios and auxiliary motors. At low power a generator may be inadequate but it will function without a battery. An alternator needs battery voltage through its field coil. Then it will function even at very low engine power.

Each electrical circuit in the airplane will have a fuse or circuit breaker for protection. If something fails to work properly first confirm the switch position and then the fuse or breaker. The ampere meter will show the proper functioning of the electrical system and sometimes the load imposed. Many aircraft have an external battery plug, which will allow an external battery to be used to start the engine. The alternator will still require at least a partially charged battery.

Adjustable air vents can be set to admit outside air into the cockpit. The engine exhaust system has a heater muff, which can conduct hot air into the cockpit. If there is a leak in the exhaust system carbon monoxide can enter as well. Always mix heater air with fresh air as well has having a detector disk.

There is no reason for the small aircraft to be exposed to structural ice. Do not fly in or into weather conditions conducive to icing. The only ice prevention device on a small aircraft might be the pitot heat on the airspeed system. This should be turned on when in precipitation as a preventative measure.

The vacuum system usually runs off an engine driven pump. The cockpit has a vacuum pressure gauge that should read between 4.5 and 5.4 for normal operation. This pressure is used to operate to attitude and heading indicators. Other things may work from this as well. At vacuum pump failure the heading indicator will begin to spin and the attitude indicator will begin to tilt and remain tilted. If in IFR conditions, cover up any failed instrument.

The aircraft radio is VHF   AM, which reduces interference but operates essentially on line of sight from 118.0 to 135.975 kHz. The current 720 possible frequency selections can be as selective as 25/1000ths of a kHz, such as 122.725, and 122.975 which are the 1992 additions to UNICOM frequencies. 122.72 and 122.97 may be assumed to have the additional 5 to the thousandth place. Many aircraft have an avionics master switch to reduce the frequency of radio on/off switch failure. It is best to make an initial setting of the radio volume and leave it. Use the panel switch to turn off the speaker or phones.

The navigation side of the radio goes from 108.0 to 117.9 MH AM. There is an additional switch, which allows a .05 sideband to increase the reception of navigational aids operational verification/identification code. No NAVAID should be used without such identification. The use of the NAV side to receive voice from an FSS is now obsolescent.

Reference FAR Part 91

P Knowledge of required instruments and equipment for day/night VFR Procedure to flying with inoperative instruments and equipment. How to get special flight permit. Not required of older aircraft G.A.before 1979

Permanent Records
Total time on airframe, engine, propeller, since last overhaul of items required to be overhauled.

Status of life-limited parts, inspections, airworthiness directives.

Copies of all FAA Form 337s with duplicate to FAA in OKC

IFR records on pitot/static system, altimeter, transponder, encoder and VORs.

Inoperable equipment must be entered into maintenance logs.

Engine Logs
Does not change prior history. Time is added as "since overhaul". Work by FAA licensee.

Time in service begins anew. Rebuild must be by FAA approved depot.

FAR 43.11(a)(b) Type, description, date, total time, signature, certificate type and number; approval or disapproval for return to service Advisory Directives (Ads) compliance (work, inspection, repair) completed and signed off

100 hour, minor alterations. A & P sign off required

Annual or progressive, major alteration AI sign off required and compliance with ADs.

Not in FARs but require A & P signoff

Getting an MEL to Use
--The MEL is a list of all things that may be inoperative without rendering the aircraft un-airworthy.
--Using the proper procedures on selected inoperative items the aircraft may be legally flown.
What to do:
--Get the Master MEL specific to your aircraft from the FAA FSDO
--Design a Proposed MEL from this Master list.
--Your proposal will be checked by the FAA specialists.
--Any approval given in a Letter of Authorization must be based upon past experience and operational history.
--MEL’s and LOA’s are aircraft-specific and equivalent to Supplemental Type Certificate (STC)
--A preamble is followed by operations and maintenance procedures then you can get the LOA.

Operating without a (MEL)
Minimum Equipment List
Most older aircraft have been certified without a MEL but everything operational when the aircraft was certified must be operational for flight--including the cigarette lighter and tire pressure.

Without an MEL any inoperative item must be removed or deactivated and then placarded. A certificated mechanic must do the work, adjust the weight and balance, complete FAA Form 337 and approve for return to service.

MEL Decision Sequence:
The pilot recognizes inoperative instruments or equipment

Questions with Yes and No Answers:
Is the item required by MEL or kinds of operations list?

If "yes" aircraft is unairworthy!
If "no" 91.205, 91.213(d)(2)(ii)

Is the inoperative item required for this flight?

If "yes" aircraft is unairworthy!
In "no" 91.213(d)(2)(ii)

Is the item required by airworthiness directive (AD)?

If "yes" the aircraft is unairworthy
If "no" 39, 91.213(d)(2)(iv)

Is the item required by FAR 91.107, 91.171, 91.185, 91.205, 91.207, 91.209 etc 91.213(d)(2)(ii)

If "yes" the aircraft is unairworthy
If "no"

The item must be removed or deactivated and placarded inoperative

91.213(a)(3)(i), 91.213(a)(3)(ii)

Pilot must determine that the item does not constitute a hazard under the conditions of the flight. Pilot may perform work that comes under preventive maintenance. Item: Under the strictest interpretation of the FARs, it is almost impossible to fly a legal, airworthy aircraft.

FAR 91.213 is distinct from FAR 91.205 which just lists what is required for specific operations. 91.213 says you can’t fly with inoperative instruments or equipment. Without an MEL, the alternative is in subsection (d), which requires a placard, plus deactivation or removal. Subsection (d) places total responsibility on the pilot.

1. The pilot must determine hazard potential, if any.
2. Determination may be made by certified mechanics.
3. Owner/operator must confirm if required for selected flight operation.
4. Refer to POH for selected flight operation.
5. If not required, deactivate and placard or remove by certified maintenance person who must make required placard and logbook entries.
6. Inoperative placard must be replaced at each required inspection.

--FAR 91.213
sets what must be done before flight.
--First the inoperative item must be identified.
--Check to see if item is or is not on MEL.
--Check FAR 91.205 to see if item is day VFR required.
--Check to see if item is required by airworthiness directive (AD)
--Check to see if item is FAR required under 91.205; 207; or 213.
--1/8 inch lettering must placard the item as INOPERATIVE, REMOVED or DEACTIVATED
--Pilot must declare aircraft airworthy.

The main difference between a 100-hour inspection and annual inspection is that the airframe and power plant mechanic can sign off the 100 hour but the annual sign-off requires inspection authorization. While an in-flight operational check may not be required it is very worthwhile. The pilot making the flight should sign the logbooks.

Minor FAR 43.9(a) compliance
Work done, date completed, certificate type/number, signature.

TT (total time) not required

FAR 43.9 requires that the person performing preventive maintenance must record the work in the maintenance records. The record must contain a description of the work, the date of the work, the name of the person doing the work, and approval or disapproval the aircraft for return to service.

Return to service by FAR 65.95

Repair stations
FAR 145 for propellers, instruments and avionics

Need not be listed in logbook but separate discrepancy list must be signed off

Airworthiness Directives (ADs)
FAR 91.403(a) requires that an AD compliance record be kept
. Some AD are one-time and others recurring. They notify aircraft owners and others of unsafe conditions and what must be done to operate the aircraft. ADs may be an emergency, which requires immediate compliance or less urgent nature with some time slack allowed. ADs are FAR’s and must be complied with unless exempted. There is no ‘overfly allowance as may exist with inspections. FAR 91.417 requires a record be maintained showing status of all ADs applicable to an aircraft. This often is on a separate sheet.

Service Difficulty Reports (SDRs)
SDRs are a mechanics’ report on maintenance problems. These are collected by the FAA and aircraft manufacturer and passed on to maintenance facilities as ADs (Airworthiness Directive) or as a maintenance suggestion. SDRs make up about 10% of all reported problems.

The most common items reported are those under the greatest stress. Exhaust valves, crankshaft weights, and valve train problems are most common. Cylinder reports relate to cracks at exhaust port area. Magneto problems relate to failed coils. Certain engine models are subject to specific reports related to inherent weakness such as case cracking in Continentals. Lycoming has engines with valve wobble problems. If ever you own an airplane, get an SDR listing for it.

Service Bulletin
Issued by manufacturer about service problems and solutions. The solution is not mandatory as with an AD.

Maintenance Records
The owner/operator is responsible for all required maintenance, inspections and logbook entries on an aircraft. FAR 43 gives entry examples of ‘appropriate" entries. This includes compliance with the FARs such as FAR 91.403(a) and FAR 91.405. 91.405 requires maintenance sufficient to keep aircraft airworthy. The owner-operator must retain the log books, be responsible that proper entries are made, and be able to make them available to authorities.

All records of maintenance and inspections require that entries say what has been done, the date of completion, signature and certification of the one doing the work and sign-off. A proper sign-off applies only to the work done. An inspection does not make the aircraft airworthy. An aircraft is airworthy only when work specified in the inspection as being required is completed and signed-off.

FAR 91.213(d)(2) covers inoperative equipment. This requires that any inoperative instrument or equipment have a signed placard FAR 43.11 as well as logbook entries regarding the action taking. Approval for return to service is required. Maintenance is the owner/operator responsibility; airworthiness is the pilot's.

FAR 91.7(b) "The pilot in command of a civil aircraft is responsible for determining whether the aircraft is in a condition for safe flight." If anything untoward happens the FAA gets to second-guess the pilot's decision. The regulations on maintenance and inspections are in FAR 91.403(a) and 91.405. 91.3 states: "The pilot in command of an aircraft is directly responsible for, and is the final authority as to, the operation of that aircraft. Again, if anything untoward happens the FAA gets to second-guess the pilot's decision. The PIC determines airworthiness in the preflight, review of paperwork and checking aircraft maintenance records. The aircraft must meet and continue to meet it original type design data unless approved changes are made.

Airworthiness Directive
(AD)Compliance Record
Aircraft No: Make: Serial Number

Aircraft Model:_______________________________________________________________

AD # Date Subject Compliance Method of Date of Airframe Component One-time Recurring Next Authorized and Received Due Compliance Compliance Total Time Total time in Compliance Signature

Amend Date/Hours Service at Service at Date/Hours Certificate

Number Other Other Type & #

Aircraft Record keeping Requirements of Part 91

Regulation Required Required Recordation Retention

Records Entry Location Requirement

91.411 Altimeter and Encoder Date and maximum altitude Maintenance Log 24 months

Signature, # Permanent

91.413 Transponder tests Test, date, signature # Maintenance log 24 months


91.417(a)(i ) Preventive, alternations Work performed, date completed Maintenance log Until repeated,

91.417(b)(i) 100 hr, annuals, required, Signature, certificate # of person Component log suspended, or approved inspections returning aircraft to service for one year

91.417(a)(i) Total time in service Identification /serial number Maintenance log Indefinite

91.417(b)(i) airframe, engines, Total time since new/overhauled Component log
propeller .

91.417(a)(2)(ii) Status of life-limited parts Identification /serial number Maintenance log Indefinite

91.417(b)(2) airframe, engine, propeller, Total time since new/overhauled Permanent record
or appliance

iii Time since last overhaul Identification/serial number Maintenance log Indefinite

as required on time basis Total time of service since Permanent record

________________ last overhaul .

iv Inspection status, time Type/time of last inspection Maintenance log Indefinite

since last defects found, items deferred Permanent record

v Status of ADs, time/ date DA number, revision date, Maintenance log Indefinite

when next required date of compliance, method AD Compliance record

and time/date of next action Permanent record

Signature/ Certificate # .

vi Form copies prescribed by Specified on Form 337 Form 337 attached Indefinite

FAR 43.9(a) for major alternation

Pilot/Owner Maintenance
Keeping an aircraft clean greatly improves both its appearance and its performance. When you clean an aircraft you learn a great deal about its construction and maintenance. You become aware of small defects and maintenance problems. Cleaning protects the thin layer of paint from the corrosion potential of dirt and airborne chemicals. Detergent and water are the best aircraft cleaners. If heavy grease must be removed be sure to obtain something other than a household cleaner should be used. Specifically, get a degreaser designed only for aircraft use.

Only aircraft type cleaners should be used on plastics and Plexiglas. Using a dry cloth on Plexiglas will cause an electrostatic charge to develop what will attract dust. Washing is the best cleaning method for Plexiglas.

Oils and solvents from the ground or in the air damage natural rubber more than synthetic. Light, especially sunlight will affect the durability and elasticity of rubber. Keep your tires both clean and out of direct sunlight. Keep all rubber surfaces free of hydrocarbons.

Frequent use of a specific aircraft gives the pilot an opportunity to determine what normal operation feels and sounds like. Knowing this makes early detection of abnormal conditions more easily detected.

WD-40 and Cleaning
The use of WD-40 is not recommended on aircraft. It is not recommended because only a light lubricant is left after the solvents evaporate. Use Kroil or ACF-50 available through aircraft parts houses. The use of steam cleaning and pressure washers on aircraft is not good practice since lubrication points are not sealed. Open bushes, pivot points must be dismantled to grease. Pressure washes flush out the oil and will wet the interior making it subject to corrosion.

Most dangerous thing in aviation:
A pilot with a tool box." or "A politician with a good idea."

FAR 43.7(f) says that a Part 61 pilot may do preventative maintenance on an aircraft used in Part 91 operations provided it does not involve complex assembly operations. The pilot can approve for return to service after work under FAR 43.3(g) 29 items are listed. The complete index is in FAR Part 43, Appendix A.

The pilot can:
Replace safety belts
Remove, install and repair tires
Replenish hydraulic fluid in reservoir
Replace, clean and space spark plugs
Replace and service batteries (Not ELT)
Replace bulbs, reflectors and lenses in lights
Trouble shoot and repair landing light circuits
Replace defective safety wiring and cotter keys
Servicing landing gear shocks by adding oil or air

FAR 91.7 makes the pilot responsible for the airworthiness of an aircraft. Assumption of this responsibility carries with it responsibility to become and remain knowledgeable about the aircraft and its systems. The owner/operator is responsible for the actual financing of the maintenance. A certified mechanic must inspect any work done and make required entries in the records of the aircraft. FAR 43.3(d) requires that the mechanic personally observe the work and be available while the job is in progress. However, the FAA gets to second-guess all actions by these parties if something occurs.

The best care you can show toward your engine is to use it along with some good pilot procedures. A sitting engine will rust and corrode. Avoid descents with reduced power which may cause shock cooling; high rpm starts which fail to provide required initial lubrication; and, excessive leaning at high rpm which will burn exhaust valves.

Partial MELs
Retractable Gear
--Landing gear motor
--Gear position lights/indicators
--Gear warning system

--Cockpit lights
--Taxi light
--Landing light
--Position lights

Navigation Instruments
--Airspeed indicator
--Vertical speed indicator
--Magnetic compass
--Attitude indicator
--Turn and slip indicator
--Directional gyro
--Navigation devices

Day VFR 91.213(b)
--Felt Mamas Foota
--Fuel Gauge
--Landing gear indicators
--Manifold pressure gauge.
--Airspeed indicator
--Magnetic compass
--Flotation device
--Oil temperature gauge
--Oil pressure gauge
--Temperature gauge (liquid cooled engines)
--Anti-collision light

Night VFR 91.213 (C)
--Fuses + spares or 3 spares each
--Landing Light (For hire)
--Alternator or source of energy.
--Position lights

MMEL and a MEL
A MMEL is a list of equipment and instruments that may be inoperative on a specific type of aircraft. It is not specific to serial or registration number. A MEL is specific to a particular make and model by serial and registration number and is developed by using the MMEL. The FAA considers the approved MEL as a supplemental type certificate (STC), permitting the aircraft to operate with certain inoperative instruments and equipment.

An approved MEL includes the procedures document and a letter of authorization (LOA) from the flight standards district office (FSDO) and must be carried in the aircraft. If an aircraft has an approved MEL, it must be used for inoperative instruments and equipment instead of the provisions stated in FAR 91.213(d) *for aircraft without an approved MEL. To learn more on how to obtain a MEL for your aircraft, see Advisory Circular 91-67. For additional information on flying with inoperative equipment, see AOPA Online

Guide for Best Maintenance of Aging Aircraft 
---2000 average age of 150,000 singles is more than 30 
---2020 average will be 50 ---Newer aircraft are not cost competitive 
---Biggest lack of safety factor is situational awareness. 
---Older aircraft have no standards for fatigue or continued airworthiness 
---Little is known about the effect of aging in older aircraft 
---We have learned about corrosion and some generalities ---Numerous factors influence the aging process 
---There are type differences and individual aircraft difference 
---Maintenance records are best source of information. 
---Type continued airworthiness information is best obtained in ‘type clubs’ 
---The gathering, recording and sharing of information increases life and safety 
---Best info is records research and special attention inspections 
---Research sets baseline as to how best care for an airplane. 
---Logbook entry copy is available through FAA by N-number of aircraft 
---Usege and maintenance history of aircraft is half the value of the aircraft 
---FAA gets records of AD compliance, supplemental type certificates and alternations per 337 form
---Type Certificate Data Sheets (TCDS) baseline technical and performance and specifications
---Airworthiness Directives (AD) records of manditory action to correct unsafe condition 
---Special Airworthiness information Bulletins (SAIB) is not mandatory but informational
---Service Bulletins/Letters are manufacturers’ service issues of improvement 
---Service Difficulty Reports (SDR) FAA database of problems submitted 
---National Transportation Safety Board (NTSB) is searchable database matches cause to accidents

---General Aviation Airworthiness Alerts are AC43-16A warnings of a problem or trend to problems
Supplemental Type Certificates (STC) upgrades of equipment or design. 

Inspection Considerations 
---Ground time vs. air time 
---Geographic considerations and temperature extremes 
---Activity vs. inactivity such as hangar’d or not 
---Special usage like freight dog or aerobatics Age Related Inspection 
---Goes beyond the 14CFR 43.15, Appendix D requirements 
---Based on identified types of problems and places 
---May be based upon manufacturer’s recommendations 

Three Groups of Four 
General area: avionics, controls, electrical, empennage 
Engine: fuel system, fuselage, instruments, landing gear 
Modifications: propeller, repairs, systems, wing 

---Areas of Interest: Calendar age, corrosion, wiring, electrical connectors, seats, fuel and hydraulic plumbing and control cables 
---Why inspections are necessary, items of special concern, critical areas, accessibility 
---Keep inspection checklists with logbooks References http://data.aopa2org/associations 

AC20-106, Aircraft Inspection for the General Aviation Aircraft Owner 
AC 43-4A, Corrosion Control for aircraft AC 43-12A, Preventative Maintenance 
AC 43,13-1B Acceptable Methods, Techniques and Practices – Aircraft Inspection and Repair Make an 

Inspection Chart 
Component     Service Letters       Date Last Inspected     Findings and notes 
Up to 200+ items checked for corrosion, connection, operation, cracks, accuracy, condition, indications, attachment, leakage, locking, wear, calibration, paper work, additional requirements, records review, certification, drains,

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Related Pages 2.25 5.72, 5.74
Continued on Page 2.25 Engine and Airframe Technicalities